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  In 1869, Friedrich Miescher isolated "nuclein," DNA with associated proteins, from cell nuclei. He was the first to identify DNA as a distinct molecule.
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  Theodore Boveri describes cell division to produce gametes (meiosis).
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  Walter Sutton deduces that chromosomes separate for reproduction. This becomes the basis for the chromosome theory of inheritance, to become official two years later.
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  Griffith's experiment discovering the "transforming principle" in pneumococcus bacteria
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  Oswald Avery's team proves that DNA, not protein, is the genetic molecule.
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  Erwin Chargaff’s research paved the way for the discoveries of DNA’s structure and its method of replication.
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  Rosalind Franklin and Maurice Wilkins contributed to the discovery of the structure of DNA.
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  Hershey and Chase did two experiments to prove that DNA is the carrier of the genetic information.
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  James Watson and Francis Crick solved the structure of DNA.